1. Field of the Invention
The present invention relates to a tubular spring hinge assembly, and more particularly to a tubular spring hinge assembly that may efficiently eliminate noise due to friction when the two tubes are rotated relatively by the door plate.
2. Description of the Related Art
A conventional spring hinge in accordance with the prior art shown in FIGS. 1 and 2 comprises an upper tube 1, a lower tube 2, a torsion spring 3, a central shaft 4, and two tension adjusting seats 5.
The upper tube 1 has an insertion section 101 pivotally inserted into the lower tube 2. The upper tube 1 has a side provided with an ear plate 102, and the lower tube 2 has a side provided with an ear plate 202. The torsion spring 3 is mounted in the upper tube 1 and the lower tube 2. Each of the two tension adjusting seats 5 is mounted on the top of the upper tube 1 and the bottom of the lower tube 2. The central shaft 4 is mounted in the torsion spring 3, and has two ends each passed through each of the two tension adjusting seats 5 and each screwed with a cover 401. Each of the two tension adjusting seats 5 is formed with a positioning hole 501 for mounting a metallic protection tube 502. Each of the two ends of the torsion spring 3 is inserted into the metallic protection tube 502. Each of the two tension adjusting seats 5 has a periphery formed with multiple adjusting holes 503 for insertion of a first end of a pin 504 whose second end is rested on the side face of each of the two ear plates 102 and 202. Each of the two tension adjusting seats 5 may be rotated by each of the two ear plates 102 and 202, to twist the torsion spring 3 which may store the energy, so that the door may be restored automatically after being opened.
After the conventional spring hinge is mounted between the door plate and the door frame, the upper tube 1 and the lower tube 2 may be rotated relatively when the door plate is opened or closed, so that the insertion section 101 of the upper tube 1 is rubbed with the lower tube 2, thereby producing noise.
The present invention has arisen to mitigate and/or obviate the disadvantage of the conventional spring hinge.
The primary objective of the present invention is to provide a tubular spring hinge assembly including a connecting tube for connecting two tubes, and two separation tubes mounted between the connecting tube and each of the two tubes. Each of the two separation tubes is made of a wear-resistant plastic, thereby efficiently eliminating noise due to friction when the two tubes are rotated relatively by the door plate.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.